1. Field of the Invention
The present invention relates to a switching mechanism for switching a position of a movable member and an electronic instrument using the same such as an electronic instrument equipped with an imaging device.
2. Description of Related Art
Various types of the electronic instruments equipped with an imaging device, such as a notebook personal computer, a personal digital assistant (PDA), and a cellular phone have recently been developed. It has been indispensable to improve performance of the imaging device and reduce its size. Especially if a small-sized imaging device is incorporated in an electronic instrument, the performance thereof is liable to deteriorate due to lens aberration etc when optical elements are downsized. Thus, the lens itself has its limits in miniaturization. This results in simplifying a member for holding optical elements and a driving mechanism therefor.
Conventionally, as a switching mechanism for switching a position of an optical element, for example, a filter or a lens, in an imaging device, it has been disclosed that an arm is attached to a member subject to movement so that the arm may be manually moved or the arm is moved using a motor as a driving source.
In such the switching mechanism, however, to manually drive the arm attached to a moving member, it is necessary to mount the member (arm or holding frame) on a chassis of an electronic instrument, so that this member acts as a protrusion on the chassis. This prevents miniaturization, thus damaging appearances problematically. Further, such a configuration that the arm can be driven using a motor in the chassis requires a space for housing the motor and increases a weight thereof as a whole.